Electric cars and other electric-motor driven vehicles are known in the art, including so-called hybrid vehicles which use one or another combination of electric motor and fossil-fuel powered motor, which is in some cases a gas turbine, such as disclosed in U.S. Pat. No. 3,477,537, for an ELECTRIC MOTOR-DRIVEN AUTOMOBILE, issued Nov. 11, 1969, to the inventor of the present invention. Later patents disclosing subject matter in the same are include: U.S. Pat. No. 6,213,234 to Rosen et al., for a VEHICLE POWERED BY A FUEL CELL/GAS TURBINE COMBINATION; U.S. Pat. No. 5,826,673 to Bates et al., for a HYBRID ELECTRIC PROPULSION SYSTEM USING A DUEL SHAFT TURBINE ENGINE; U.S. Pat. No. 5,762,156 also to Bates et al., and also for a HYBRID ELECTRIC PROPULSION SYSTEM USING A DUEL SHAFT TURBINE ENGINE, and having essentially the same disclosure as the above; U.S. Pat. No. 5,765,656 to Weaver, for a HYBRID ELECTRIC MOTOR VEHICLE DRIVE; and U.S. Pat. No. 5,746,283 to Brighton, for an ELECTRIC PROPULSION SYSTEM FOR A VEHICLE. All of these U.S. patents disclose using electric motors, and in some cases uses more than one electric motor, one for each of at least two wheels; also, all of these typically include at least two sources of power for the electric motors, with one being a turbine, and more specifically a gas turbine except for the '283 patent, where the turbine is instead a wind turbine, and the other being either a fuel cell or a battery. The turbine typically drives an electric generator, which in turn drives the one or more electric motors or charges the electric power storage device—the fuel cell or battery—or does both, sometimes doing one under some driving conditions and doing the other under other driving conditions. For example, the electric motor-driven automobile disclosed in the '537 patent to the inventor of the present invention uses either a gas turbine driving an electric generator to provide electric current to a motor for each wheel, or a battery for the same purpose, and can use the output of the electric generator driven by the gas turbine to drive the battery.
Of the above-mentioned patents, besides the '537 patent to the inventor of the present invention, only the '234 patent to Rosen et al and the '283 patent to Brighton disclose a vehicle with more than one electric motor. The '234 patent to Rosen et al discloses a vehicle having a separate electric motor 18 for each of two rear wheels 16; each electric motor 18 is drivingly connected to a respective wheel 16 through a respective drive train 20. An automobile according to the '234 patent uses a gas turbine 26 to drive an electric generator 24 for providing electric power to the electric motors 18. Instead of always relying on electric power from the generator driven by the gas turbine, the electric motors attached to each wheel can receive current from a fuel cell 22. (A fuel cell is not recharged by electric current, and instead must be fueled with for example hydrogen or material from which hydrogen can be extracted.) The '234 patent also discloses using a flywheel 80 and possibly also a battery 82, both of which can be used for storing energy, including energy recovered for example during braking. A power controller 30 is responsive to a control or “demand” signal, such as an acceleration or brake signal caused by a driver, to regulate the electric motors 18. The power controller 30 controls the motor torque by regulating a delivery of hydrocarbon fuel and air to both the fuel cell 22 and the gas turbine 26. In low-load conditions, where the energy needed is less than the maximum electrical power output of the fuel cell 22, the power controller 30 causes the electricity needed by the motor to be generated by the fuel cell and by the gas turbine utilizing fuel cell exhaust gases. When the vehicle's power requirements exceed the output capacity of the fuel cell, the power controller causes additional hydrocarbon fuel and compressed air to be supplied to the gas turbine to generate additional power as needed by the vehicle up to a maximum sustainable power level.
As mentioned, the '283 patent to Brighton also discloses a vehicle with four electric motors 5, one for each wheel for applying torque to the wheel. Brighton discloses having each electric (propulsion) motor 5 connected to an axle 120 to drive its respective wheel 130. The motors 5 can be connected directly to the wheels 130 or can be connected through a speed control mechanism 140. Leads 105 connect to a main generator. Leads 150 connect to a power reserve module 102. A vehicle according to Brighton has a control device that diverts power from the main generator output to a stored power unit, such as a battery pack, to recharge and maintain the stored power unit when operating conditions permit.
Besides hybrid vehicles using turbine engines as one power source, major automobile manufacturers, including Honda and Toyota, are now developing gasoline-electric hybrid vehicles. In these cars, a transmission is turned by, under some conditions, both a gasoline engine and an electric motor, and the transmission then turns the wheels of the vehicle in the same way as is done conventionally. (Thus, for such hybrid vehicles, there is only one electric motor providing a driving force/torque for all of the drive wheels, of which there are always at least two.)
In all of the prior art known to the inventor, even though according to some of the prior art a vehicle may have an electric motor applying torque to one wheel and another electric motor applying torque to another wheel, there is no disclosure of a vehicle having what is here called a distributed electric motor arrangement, i.e. at least two electric motors acting under the control of a controller that in effect causes each motor to provide a torque coordinated with the torque applied by the other motors, in much the same way as a legged or winged animal coordinates commands to the muscles causing its legs or wings to move. Such an arrangement—having multiple, distributed motors—is more survivable than the present single-thread arrangement—one motor and one transmission—since whereas in the present arrangement if either the motor or the transmission fails, the vehicle stops, in a vehicle with a distributed motor, both engines and their respective transmissions would have to fail to stop the vehicle.
The prior art also teaches what has come to be known as “drive-by-wire” technology, which refers to a way of causing a vehicle to accelerate, brake, and turn without using mechanical linkages interfacing the driver and the vehicle drive assembly, but instead using electrical linkages, i.e. wires. However, such vehicles according to the prior art nevertheless use a single engine and transmission for applying torque to each of the drive wheels.
Thus, what is needed is a vehicle having a distributed motor/motor system, and ideally, a vehicle that would have a control system coupled to the motor elements in a way that is relatively highly unlikely to fail, compared to the mechanical linkages in automobiles according to the prior art.